Removing backup song library from iTunes library

IF you are into writing scripts, it should be fairly easy to do one for this. However assuming that is not the case...

Is your second drive removable?

If so, a kludge would be to start iTunes with it unplugged, now all the tracks you don't want will be dead tracks.

These could be removed with one of Robert Jacobson's scripts - itunes removenotfound
at:
http://home.comcast.net/~teridon73/itunesscripts/

You need to download the EXE version and then when you run it select itunes removenotfound then next select library.

I would backup your library files before playing around like this:

Backup the iTunes Library Files

The library files are in:
My Documents\My Music\iTunes

Close iTunes and wait about 30 seconds.
Copy iTunes Library.itl and iTunes Music Library.xml somewhere else e.g. into the Previous iTunes Libraries folder.

To restore, with iTunes closed drag the current itl and xml file from the iTunes folder to the desktop, then copy the backup iTunes Library.itl into the iTunes folder. The xml file isn’t necessary but can come in handy if the library needs to be recreated and the itl file is causing problems.

You don't need to move the backup library, just rename the header folder so the path changes, then iTunes won't be able to find it.

Yes, iTunes doesn't do folder monitoring so once a track is removed from the library, it won't be automatically added back.

Just a couple of points, your question asked about removing tracks located on your backup drive. Have you checked that that is where they actually are? You should see the path in Get info or show in Windows explorer. If you add tracks to your library with your preferences set to "Copy to iTunes Music folder when adding to library..." checked, the duplicate tracks will not be on your backup drive and a different solution is required.

Also presumably the location of your iTunes Music folder as set in Edit>Prefrences>Advanced>General is on your c:drive?

Yes that works fine, but you lose all your metadata such as counts, ratings and play lists.

Perhaps I should have given that as an option. Just close iTunes and drag iTunes Library.itl out of your iTunes folder to your desk top. Open iTunes and you will have an empty library.